For precision machinery, it is often necessary to have bearings of very high stiffness, i.e., bearings of sufficient rigidity so that the bearing gap does not vary under changes in load. Gas pressure bearings are often used for this purpose, particularly for instrument components that must be moved easily and with extreme precision on a support. In order to attain the required precision, it is necessary that highly rigid bearings be used, whereby the bearing span is maintained substantially constant independent of the load on the bearing.
A gas pressure bearing of this type is disclosed in U.S Pat. No. 4,560,213, and it consists of a base element that is provided with a gas inlet and connected rigidly with a membrane. The connecting elements are configured in such a manner that they act as rocker bearings and permit deformation of the membrane--specifically its concave deformation--as a result of the bearing pressure. The total rigidity of this prior art gas pressure bearing is determined substantially by its mechanics, i.e., the mechanical connection between the base element that forms its bearing and the component to be supported. Further, the rocker bearings supporting the deformable membrane are somewhat elastic, having a disadvantageous effect on total rigidity..
Therefore, the invention herein is directed to the creation of a gas pressure bearing that is distinguished by (a) extremely high total rigidity, (b) an extensive load range, and, in addition, (c) only a few simple components.